Communication terminal device, communication device, communication network server and method for controlling

ABSTRACT

In various aspects of this disclosure, a communication terminal device may be provided. The communication terminal device may include a cellular wide area radio communication technology circuit. The cellular wide area radio communication technology circuit may be configured to provide a communication according to a cellular wide area radio communication technology. The communication terminal device may further include a circuit. The circuit may be configured to provide a direct communication terminal device to communication terminal device communication bypassing a radio access network according to information received via the radio access network. The communication terminal device may further include a message generator. The message generator may be configured to generate a message to transmit to a base station. The message may include at least one message field specifying information about at least one capability to provide the direct communication terminal device to communication terminal device communication of the communication terminal device. The message may be generated for a network communication protocol.

TECHNICAL FIELD

The present disclosure relates to a communication terminal, a networkcomponent, a base station and a method for communicating.

BACKGROUND

Radio communication terminal devices may directly communicate with basestations in a cellular radio communication system. Furthermore,communication terminal devices that are furthermore provided with ashort range wireless transceiver, may communicate directly with othercommunication terminal devices nearby bypassing the base station(s) of acellular radio communication system.

Radio communication terminal devices (e.g. User Equipments (UEs)) thatare residing in coverage of e.g. an LTE-FDD (Long Term EvolutionFrequency Division Duplex) cell, and want to engage in a direct e.g.TDD-based (Time Division Duplex) UE-to-UE communication (D2D) in one ofthe frequency bands of the cell may be exposed to interference caused bytraffic over the air interface (Uu interface) in the respective cell. Atthe same time, the D2D traffic over the UE-to-UE interface may alsocause some, e.g. local interference for other UEs being served over theUu interface.

SUMMARY

A communication terminal device may be provided. The communicationterminal device may include a cellular wide area radio communicationtechnology circuit. The cellular wide area radio communicationtechnology circuit may be configured to provide a communicationaccording to a cellular wide area radio communication technology. Thecommunication may be a cellular wide area radio communication betweenthe communication terminal device (e.g., a mobile device) and acommunication device (e.g., a base station) of a cellular wide arearadio communication network. The communication terminal device mayfurther include a circuit. The circuit may be configured to provide adirect communication terminal device to communication terminal devicecommunication bypassing a radio access network according to informationreceived via the radio access network. The communication terminal devicemay further include a message generator. The message generator may beconfigured to generate a message for transmission to a base station. Themessage may include at least one message field specifying informationabout at least one capability to provide the direct communicationterminal device to communication terminal device communication of thecommunication terminal device. The message may be generated for anetwork communication protocol.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like reference characters generally refer to the sameparts throughout the different views. The drawings are not necessarilyto scale, emphasis instead generally being placed upon illustrating theprinciples of the invention. In the following description, variousembodiments of the invention are described with reference to thefollowing drawings, in which:

FIG. 1 shows a communication system;

FIG. 2 shows a state diagram;

FIG. 3 shows a protocol structure;

FIG. 4 shows a first protocol structure and a second protocol structure;

FIG. 5 shows a communication system in more detail;

FIGS. 6 a and 6 b show diagrams illustrating the principles of twoduplex methods;

FIG. 7 shows a communication system;

FIG. 8 shows a communication terminal device;

FIG. 9 shows a flow diagram illustrating a UE capability transfer;

FIG. 10 shows a communication terminal device;

FIG. 11 shows a communication device, e.g. a base station;

FIG. 12 shows a communication network server; and

FIG. 13 shows a flow diagram illustrating a method for controlling acommunication terminal device.

DESCRIPTION

The following detailed description refers to the accompanying drawingsthat show, by way of illustration, specific details and embodiments inwhich the invention may be practiced.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration”. Any embodiment or design described herein as“exemplary” is not necessarily to be construed as preferred oradvantageous over other embodiments or designs.

The components of the communication device and/or the communicationterminal device (e.g. the oscillator, the accuracy determiner, thesignal detector, the controller) may for example be implemented by oneor more circuits. A “circuit” may be understood as any kind of a logicimplementing entity, which may be special purpose circuitry or aprocessor executing software stored in a memory, firmware, or anycombination thereof. Thus a “circuit” may be a hard-wired logic circuitor a programmable logic circuit such as a programmable processor, e.g. amicroprocessor (e.g. a Complex Instruction Set Computer (CISC) processoror a Reduced Instruction Set Computer (RISC) processor). A “circuit” mayalso be a processor executing software, e.g. any kind of computerprogram, e.g. a computer program using a virtual machine code such ase.g. Java. Any other kind of implementation of the respective functionswhich will be described in more detail below may also be understood as a“circuit”.

The following detailed description refers to the accompanying drawingsthat show, by way of illustration, specific details and aspects of thisdisclosure in which the invention may be practiced. These aspects ofthis disclosure are described in sufficient detail to enable thoseskilled in the art to practice the invention. Other aspects of thisdisclosure may be utilized and structural, logical, and electricalchanges may be made without departing from the scope of the invention.The various aspects of this disclosure are not necessarily mutuallyexclusive, as some aspects of this disclosure can be combined with oneor more other aspects of this disclosure to form new aspects.

The term “protocol” is intended to include any piece of software, thatis provided to implement part of any layer of the communicationdefinition. “Protocol” may include the functionality of one or more ofthe following layers: physical layer (layer 1), data link layer (layer2), network layer (layer 3), or any other sub-layer of the mentionedlayers or any upper layer.

The communication protocol layers and its respective entities which willbe described in the following may be implemented in hardware, insoftware, in firmware, or partially in hardware, and/or partially insoftware, and/or partially in firmware. In an aspect of this disclosure,one or more communication protocol layers and its respective entitiesmay be implemented by one or more circuits. In an aspect of thisdisclosure, at least two communication protocol layers may be commonlyimplemented by one or more circuits.

For reasons of simplicity, in the following, explanations will be givenusing LTE and the corresponding entities (e.g. E-UTRAN, EPC and UE),however, it is to be noted that various aspects may also be providedusing another cellular wide area radio communication technology and itscorresponding entities as will be described in more detail below.

3GPP (3rd Generation Partnership Project) has introduced LTE (Long TermEvolution) into the Release 8 version of UMTS (Universal MobileTelecommunications System) standards.

The air interface of an LTE communication system is called E-UTRA(Evolved Universal Terrestrial Radio Access) and is commonly referred toas ‘3.9G’. In December 2010, the ITU (International TelecommunicationUnion) recognized that current versions of LTE and other evolved 3Gtechnologies that do not fulfill “IMT-Advanced” (IMT: internationalmobile telecommunications) requirements could nevertheless be considered‘4G’, provided they represent forerunners to IMT-Advanced and “asubstantial level of improvement in performance and capabilities withrespect to the initial third generation systems deployed already. LTE istherefore sometime also referred to as ‘4G’ (mainly for marketingreasons).

3GPP (3rd Generation Partnership Project) has introduced LTE-Advanced(i.e. LTE with some further enhancements, such as carrier aggregationfunctionality) into the Release 10 version of its suit of communicationstandards. This is the “real” ‘4G’.

In comparison with its predecessor UMTS (Universal MobileTelecommunications System), LTE (Long Time Evolution) provides an airinterface that has been further optimized for packet data transmissionby improving the system capacity and the spectral efficiency. Amongother enhancements, the maximum net transmission rate has been increasedsignificantly, namely to 300 Mbps in the downlink transmission directionand to 75 Mbps in the uplink transmission direction. LTE supportsscalable bandwidths of from 1.4 MHz to 20 MHz and is based on newmultiple access methods, such as OFDMA (Orthogonal Frequency DivisionMultiple Access)/TDMA (Time Division Multiple Access) in downlinkdirection (tower, i.e. base station, to handset, i.e. mobile terminal)and SC-FDMA (Single Carrier-Frequency Division Multiple Access)/TDMA inuplink direction (handset to tower). OFDMA/TDMA is a multicarriermultiple access method in which a subscriber (i.e. a mobile terminal) isprovided with a defined number of subcarriers in the frequency spectrumand a defined transmission time for the purpose of data transmission.The RF (Radio Frequency) capability of a mobile terminal according toLTE (also referred to as User Equipment (UE), e.g. a cell phone) fortransmission and reception has been set to 20 MHz. A physical resourceblock (PRB) is the baseline unit of allocation for the physical channelsdefined in LTE. It includes a matrix of 12 subcarriers by 6 or 7OFDMA/SC-FDMA symbols. At the physical layer a pair of one OFDMA/SC-FDMAsymbol and one subcarrier is denoted as a ‘resource element’.

A communication system that may be provided according to various aspectsof this disclosure and which for example may be a communication systemaccording to LTE is described in the following with reference to FIG. 1.

FIG. 1 shows a communication system 100.

The communication system 100 may be a cellular mobile communicationsystem (also referred to as cellular radio communication network in thefollowing) including a radio access network (e.g. an E-UTRAN, EvolvedUMTS (Universal Mobile Communications System) Terrestrial Radio AccessNetwork according to LTE (Long Term Evolution)) 101 and a core network(e.g. an EPC, Evolved Packet Core, according LTE) 102. The radio accessnetwork 101 may include base stations (e.g. base transceiver stations,eNodeBs, eNBs, home base stations, Home eNodeBs, HeNBs according to LTE,or LTE-Advanced) 103. Each base station 103 may provide radio coveragefor one or more mobile radio cells 104 of the radio access network 101.In other words: The base stations 103 of the radio access network 101may span different types of cells 104 (e.g. macro cells, femto cells,pico cells, small cells, open cells, closed subscriber group cells,hybrid cells, for instance according to LTE, or LTE-Advanced).

A mobile terminal (e.g. UE) 105 located in a mobile radio cell 104 maycommunicate with the core network 102 and with other mobile terminals105 via the base station 103 providing coverage in (in other wordsoperating) the mobile radio cell 104. In other words, the base station103 operating the mobile radio cell 104 in which the mobile terminal 105is located may provide the E-UTRA user plane terminations including thePDCP (Packet Data Convergence Protocol) layer, the RLC (Radio LinkControl) layer and the MAC (Medium Access Control) layer and controlplane terminations including the RRC (Radio Resource Control) layertowards the mobile terminal 105.

Control and user data may be transmitted between a base station 103 anda mobile terminal 105 located in the mobile radio cell 104 operated bythe base station 103 over the air interface 106 on the basis of amultiple access method. On the LTE air interface 106 different duplexmethods, such as FDD (Frequency Division Duplex) or TDD (Time DivisionDuplex), may be deployed.

The base stations 103 are interconnected with each other by means of afirst interface 107, e.g. an X2 interface. The base stations 103 arealso connected by means of a second interface 108, e.g. an S1 interface,to the core network 102, e.g. to an MME (Mobility Management Entity) 109via an S1-MME interface 108 and to a Serving Gateway (S-GW) 110 by meansof an S1-U interface 108. The S1 interface 108 supports a many-to-manyrelation between MMEs/S-GWs 109, 110 and the base stations 103, i.e. abase station 103 may be connected to more than one MME/S-GW 109, 110 andan MME/S-GW 109, 110 may be connected to more than one base station 103.This may enable network sharing in LTE.

For example, the MME 109 may be responsible for controlling the mobilityof mobile terminals located in the coverage area of E-UTRAN, while theS-GW 110 may be responsible for handling the transmission of user databetween mobile terminals 105 and the core network 102.

In case of LTE, the radio access network 101, i.e. the E-UTRAN 101 incase of LTE, may be seen to consist of the base station 103, i.e. theeNBs 103 in case of LTE, providing the E-UTRA user plane (PDCP/RLC/MAC)and control plane (RRC) protocol terminations towards the UE 105.

An eNB 103 may for example host the following functions:

-   -   Functions for Radio Resource Management: Radio Bearer Control,        Radio Admission Control, Connection Mobility Control, dynamic        allocation of resources to UEs 105 in both uplink and downlink        (scheduling);    -   IP header compression and encryption of user data stream;    -   Selection of an MME 109 at UE 105 attachment when no routing to        an MME 109 can be determined from the information provided by        the UE 105;    -   Routing of User Plane data towards Serving Gateway (S-GW) 110;    -   Scheduling and transmission of paging messages (originated from        the MME);    -   Scheduling and transmission of broadcast information (originated        from the MME 109 or O&M (Operation and Maintenance));    -   Measurement and measurement reporting configuration for mobility        and scheduling;    -   Scheduling and transmission of PWS (Public Warning System, which        includes ETWS (Earthquake and Tsunami Warning System) and CMAS        (Commercial Mobile Alert System)) messages (originated from the        MME 109); and    -   CSG (Closed Subscriber Group) handling.

Each base station of the communication system 100 may controlcommunications within its geographic coverage area, namely its mobileradio cell 104 that is ideally represented by a hexagonal shape. Whenthe mobile terminal 105 is located within a mobile radio cell 104 and iscamping on the mobile radio cell 104 (in other words is registered witha Tracking Area (TA) assigned to the mobile radio cell 104) itcommunicates with the base station 103 controlling that mobile radiocell 104. When a call is initiated by the user of the mobile terminal105 (mobile originated call) or a call is addressed to the mobileterminal 105 (mobile terminated call), radio channels are set up betweenthe mobile terminal 105 and the base station 103 controlling the mobileradio cell 104 in which the mobile station is located. If the mobileterminal 105 moves away from the original mobile radio cell 104 in whicha call was set up and the signal strength of the radio channelsestablished in the original mobile radio cell 104 weakens, thecommunication system may initiate a transfer of the call to radiochannels of another mobile radio cell 104 into which the mobile terminal105 moves.

As the mobile terminal 105 continues to move throughout the coveragearea of the communication system 100, control of the call may betransferred between neighboring mobile radio cells 104. The transfer ofcalls from mobile radio cell 104 to mobile radio cell 104 is termedhandover (or handoff).

A handover may also occur between base stations 103 operating accordingto different radio access technologies. This is illustrated in FIG. 2.

FIG. 2 shows a state diagram 200 for exemplary system in FIG. 1.

The state diagram 200 includes the UMTS (UTRA, 3G) mobile terminalstates CELL_DCH 201, CELL_FACH 202, CELL_PCH/URA_PCH 203, and UTRA_Idle204, the LTE (E-UTRA) mobile terminal states RRC CONNECTED 205 and RRCIDLE 206 and the GSM (GERAN, 2G and 2.5G) mobile terminal statesGSM_Connected 207, GPRS Packet Transfer Mode 208, and GSM_Idle/GPRSPacket_Idle 209. Contrary to UMTS, there are only two E-UTRA RRC statesdefined for the mobile terminal 105. FIG. 2 can be seen to illustratethe mobility support between E-UTRA, UTRA and GERAN.

According to a first state transition 210, a handover may be carried outbetween E-UTRA (i.e. a base station 103 operating according to LTE) andUTRAN (i.e. a base station 103 operating according to UTMS).

According to a second state transition 211, a handover may be carriedout between E-UTRA (i.e. a base station 103 operating according to LTE)and GERAN (i.e. a base station 103 operating according to GSM).

Third state transitions 212 may occur between states of the UTRAN, theGERAN, and the E-UTRAN, e.g. in case of cell reselection without thehandover of an active call. It should be noted that state transitionsbetween states of the UTRAN and GERAN are omitted for simplicity but mayalso be possible.

Fourth state transitions 213 may occur between states of the same radioaccess technology, e.g. when a connection is released or a connection isestablished. The mobile terminal 105 is in RRC_CONNECTED when an RRCconnection has been established. If this is not the case, i.e. no RRCconnection is established, the mobile terminal 105 is in RRC_IDLE state.

The two RRC (Radio Resource Control) states RRC_IDLE and RRC_CONNECTEDin E-UTRA can be described as follows:

RRC IDLE

-   -   Mobile terminal specific DRX (Discontinuous Reception) may be        configured by upper protocol layers;    -   Mobility is controlled by the mobile terminal 105;    -   The mobile terminal 105        -   may acquire system information (SI);        -   monitors a paging channel to detect incoming calls and SI            change;        -   performs neighboring cell measurements for the cell            (re-)selection process.

RRC CONNECTED

A mobile terminal 105 is in RRC_CONNECTED when an RRC connection hasbeen established.

-   -   Transfer of unicast data to/from the mobile terminal 105;    -   Mobility is controlled by the radio access network 101 (handover        and cell change order);    -   The mobile terminal 105 may be configured with mobile terminal        specific DRX (Discontinuous Reception) at lower protocol layers.    -   The mobile terminal 105        -   may acquire system information (SI);        -   monitors a paging channel and/or SIB (system information            block) Type 1 content to detect SI change;        -   monitors control channels associated with the shared data            channel to determine if data is scheduled for it;        -   performs neighboring cell measurements and measurement            reporting to assist the network in making handover            decisions;        -   provides channel quality and feedback information to the            radio access network 101.

According to DRX the PDCCH (Physical Downlink Control Channel)monitoring activity of the mobile terminal 105 is controlled. On thePDCCH, various RNTIs (Radio Network Temporary Identifiers) can be found.

If the mobile terminal 105 is in RRC_IDLE state it is expected to listento the P-RNTI (the so-called paging indicator) transmitted on the PDCCHwhich may announce the presence of a paging message on the PDSCH. If DRXis applied in RRC_IDLE, the mobile terminal 105 only needs to monitorone Paging Occasion (PO) per DRX cycle. System Information (SI)broadcast by the base station 103 controls DRX operation by specifying amobile terminal specific paging cycle in SIB-Type2. (It should be notedthat SIB (System Information Block)-Type2 is received by all mobileterminals camping in a given radio cell, but the equation used by amobile terminal 105 in RRC_IDLE state to calculate its individual PagingOccasion (PO) has as input variable the subscriber's (i.e. mobileterminal's) unique IMSI (International Mobile Subscriber Identity)).

If DRX is configured in RRC_CONNECTED for a mobile terminal 105, themobile terminal 105 is allowed to monitor the PDCCH (Physical DownlinkControl Channel) discontinuously (in order to save energy); otherwisethe mobile terminal 105 monitors the PDCCH continuously. The RRC (RadioResource Control) layer controls DRX operation by configuring timers andparameters, for example as shown in table 1.

TABLE 1 longDRX-CycleStartOffset The value of longDRX-Cycle is in numberof sub-frames. If shortDRX-Cycle is configured, the value oflongDRX-Cycle shall be a multiple of the shortDRX-Cycle value. The valueof drxStartOffset value is in number of sub-frames. onDurationTimer Thevalue in number of PDCCH sub-frames. drx-InactivityTimer The value innumber of PDCCH sub-frames. drx-RetransmissionTimer The value in numberof PDCCH sub-frames. shortDRX-Cycle The value in number of sub-frames.drxShortCycleTimer The value in multiples of shortDRX-Cycle.

The protocols for the C-Plane and the U-Plane of the E-UTRAN 101according to LTE are illustrated in FIG. 3.

FIG. 3 shows a protocol structure 300 according to an aspect of thisdisclosure.

The LTE air interface (also referred to as Uu interface) is logicallydivided into three protocol layers. The entities ensuring and providingthe functionality of the respective protocol layers are implemented bothin the mobile terminal 105 and the base station 103. The bottommostlayer is the physical layer (PHY) 301, which represents the protocollayer 1 (L1) according to the OSI (Open System Interconnection)reference model. The protocol layer arranged above PHY is the data linklayer, which represents the protocol layer 2 (L2) according to the OSIreference model. In an LTE communication system, L2 consists ofplurality of sublayers, namely the Medium Access Control (MAC) sublayer302, the Radio Link Control (RLC) sublayer 303 and the Packet DataConvergence Protocol (PDCP) sublayer 304. The topmost layer of the Uuair interface is the network layer, which is the protocol layer 3 (L3)according to the OSI reference model and consists of the Radio ResourceControl (RRC) layer 305 on the C-Plane 307. On the C-Plane 307, there isfurther the NAS (Non-Access Stratum) protocol layer 306.

Each protocol layer 301 to 306 provides the protocol layer above it withits services via defined service access points (SAPs). To provide abetter understanding of the protocol layer architecture, the SAPs wereassigned unambiguous names: The PHY 301 provides its services to the MAClayer 302 via transport channels, the MAC layer 302 provides itsservices to the RLC layer 303 via logical channels, and the RLC layer303 provides its services to the RRC layer 305 and the PDCP layer 304 asdata transfer as function of the RLC mode, i.e. TM (Transparent Mode),UM (Unacknowledged Mode) and AM (Acknowledged Mode). Further, the PDCPlayer 304 provides its services to the RRC layer 305 and the U-Plane 308upper layers via radio bearers, specifically as Signaling Radio Bearers(SRB) to the RRC 305 and as Data Radio Bearers (DRB) to the U-Plane 308upper layers. According to LTE a maximum of 3 SRBs and 8 DRBs iscurrently supported.

The radio protocol architecture is not just split horizontally into theabove-described protocol layers; it is also split vertically into the“control plane” (C-Plane) 307 and the “user plane” (U-Plane) 308. Theentities of the control plane 307 are used to handle the exchange ofsignaling data between the mobile terminal 105 and the base station 103,which are required among other for the establishment, reconfigurationand release of physical channels, transport channels, logical channels,signaling radio bearers and data radio bearers, whereas the entities ofthe user plane 308 are used to handle the exchange of user data betweenthe mobile terminal 105 and the base station 103. According to oneaspect of this disclosure, according to LTE, each protocol layer hasparticular prescribed functions:

-   -   The PHY layer 301 is primarily responsible for i) error        detection on the transport channel; ii) channel        encoding/decoding of the transport channel; iii) Hybrid ARQ soft        combining; iv) mapping of the coded transport channel onto        physical channels; v) modulation and demodulation of physical        channels.    -   The MAC layer 302 is primarily responsible for i) mapping        between logical channels and transport channels; ii) error        correction through HARQ; iii) logical channel        prioritization; iv) transport format selection.    -   The RLC layer 303 is primarily responsible for i) error        correction through ARQ, ii) concatenation, segmentation and        reassembly of RLC SDUs (Service Data Unit); iii) re-segmentation        and reordering of RLC data PDUs (Protocol Data Unit). Further,        the RLC layer 303 is modeled such that there is an independent        RLC entity for each radio bearer (data or signaling).    -   The PDCP layer 304 is primarily responsible for header        compression and decompression of IP (Internet Protocol) data        flows, ciphering and deciphering of user plane data and control        plane data, and integrity protection and integrity verification        of control plane data. The PDCP layer 304 is modeled such that        each RB (i.e. DRB and SRB, except for SRB0) is associated with        one PDCP entity. Each PDCP entity is associated with one or two        RLC entities depending on the RB characteristic (i.e.        uni-directional or bi-directional) and RLC mode.    -   The RRC layer 305 is primarily responsible for the control plane        signaling between the mobile terminal 105 and the base station        103 and performs among other the following functions: i)        broadcast of system information, ii) paging, iii) establishment,        reconfiguration and release of physical channels, transport        channels, logical channels, signaling radio bearers and data        radio bearers. Signaling radio bearers are used for the exchange        of RRC messages between the mobile terminal 105 and the base        station 103.

Differences between the C-Plane (control plane) 307 and the U-Plane(user plane) 308 according to E-UTRA (LTE) technology are depicted inFIG. 4. The RRC protocol and all lower layer protocols (PDCP, RLC, MAC,and PHY) terminate in the eNB, while the NAS protocol layer 306terminates in the MME 109 in the EPC 102.

FIG. 4 shows a first protocol structure 400 and a second protocolstructure 410.

The first protocol structure 400 corresponds to the U-Plane and thesecond protocol structure 410 corresponds to the C-Plane.

Analogously to the illustration as shown in FIG. 3, the protocolstructures 400, 410 include a physical layer 401, a MAC layer 402, anRLC (Radio Link Control) layer 403, a PDCP layer 404, an RRC layer 405,and a NAS (Non-Access Stratum) protocol layer 406.

In the physical layer 401, the MAC layer 402, the RLC layer 403, thePDCP layer 404, and the RRC layer 405 the terminal points of thecommunication are the mobile terminal (UE) 411 and the base station(eNB) 412.

In the NAS protocol layer 406, the terminal points of the communicationare the UE 411 and the MME 413.

With LTE the UMTS air interface is further optimized for packet datatransmission by improving the system capacity and the spectralefficiency. However, the enhancements for LTE technology are notrestricted to the air interface. The core network architecture for3GPP's LTE wireless communication standard is also enhanced. Thisendeavor is commonly known as SAE (System Architecture Evolution).

SAE refers to the evolution of the GPRS Core Network, with somedifferences:

-   -   simplified architecture;    -   all IP (Internet protocol) Network (AIPN);    -   support for higher throughput and lower latency radio access        networks (RANs);    -   support for, and mobility between, multiple heterogeneous RANs,        including legacy systems as GPRS, but also non-3GPP systems        (e.g. WiMAX);

According to the SAE architecture, the main component is the EvolvedPacket Core (e.g. forming the core network of the communication system100 illustrated in FIG. 1). The Evolved Packet Core (EPC) includes:

-   -   A Mobility Management Entity (MME): The MME is the key        control-node for the LTE radio access network (E-UTRAN) and,        according to LTE, holds the following functions:        -   NAS signaling;        -   NAS signaling security;        -   AS (Access Stratum) Security control;        -   Inter CN (Core Network) node signaling for mobility between            3GPP access networks;        -   Idle mode UE Reachability (including control and execution            of paging retransmission);        -   Tracking Area List (TAL) management (for UE in idle and            active mode);        -   PDN GW (Packet Data Network Gateway) and Serving GW            selection;        -   MME selection for handovers with MME change;        -   SGSN (Serving GPRS (General Packet Radio System) Support            Node) selection for handovers to 2G or 3G 3GPP access            networks;        -   Roaming;        -   Authentication;        -   Bearer management functions including dedicated bearer            establishment;        -   Support for PWS (which includes ETWS and CMAS) message            transmission;        -   Optionally performing paging optimization.    -   A Serving Gateway (S-GW): The S-GW holds, according to LTE, the        following functions:        -   The local Mobility Anchor point for inter-eNB handover;        -   Mobility anchoring for inter-3GPP mobility;        -   E-UTRAN idle mode downlink packet buffering and initiation            of network triggered service request procedure;        -   Lawful Interception;        -   Packet routing and forwarding;        -   Transport level packet marking in the uplink and the            downlink;        -   Accounting on user and QCI (QoS (Quality of Service) Class            Identifier) granularity for inter-operator charging;        -   Uplink and Downlink charging per UE, PDN, and QCI.    -   A PDN Gateway (P-GW): According to LTE, the PDN Gateway provides        connectivity from the UE to external packet data networks by        being the point of exit and entry of traffic for the UE. A UE        may have simultaneous connectivity with more than one P-GW for        accessing multiple PDNs. The P-GW performs policy enforcement,        packet filtering for each user, charging support, lawful        Interception and packet screening. Another key role of the P-GW        is to act as the anchor for mobility between 3GPP and non-3GPP        technologies such as WiMAX and 3GPP2 (CDMA 1x and EvDO        (Evolution Data Optimized)).

In the following, the network architecture of a communication system(e.g. a 3GPP communication system) with three different Radio AccessNetworks (RANs) is described with reference to FIG. 5 (for thenon-roaming case).

FIG. 5 shows a communication system 500 according to an aspect of thisdisclosure.

The communication system 500 includes an E-UTRAN 501 and a core network502.

The communication system 500 corresponds to the communication system 100wherein in FIG. 1, the E-UTRAN 101, 501 is shown in higher detail whilein FIG. 5, the core network 102, 502 is shown in higher detail.

A mobile terminal 503 which may correspond to the mobile terminal 105may connect to the E-UTRAN 501 by means of an air interface (Uuinterface) 504.

The core network 502 includes a Serving Gateway 505, a PDN (Packet DataNetwork) Gateway 506, a PCRF (Policy and Charging Rules Function) 507,an MME (Mobility Management Entity) 508, and a HSS (Home SubscriberServer) 509, an SGSN (Serving GPRS (General Packet Radio Service)Support Node) 510.

The E-UTRAN 501 exchanges information or commands with the ServingGateway 505 by means of an S1-U interface 511. The Serving Gateway 505is coupled to the PDN Gateway 506 by means of an S5 interface 512. ThePDN Gateway 506 and the PCRF 507 may access IP (Internet Protocol)services 515 (i.e. may access, for example, corresponding servers)provided by the operator of the mobile communication system 500 by meansof an SGi interface 513 and an Rx interface 514, respectively.

The PCRF 507 is coupled to the PDN Gateway 506 by means of a Gxinterface 516. The Serving Gateway 505 is coupled by means of an S4interface 524 with the SGSN 510. The Serving Gateway 505 may further becoupled to an UTRAN (i.e. a radio access network according to UMTS) 517via a S12 interface 518. The MME 508 is coupled by means of an S6ainterface 525 with the HSS 509. The MME 508 is further coupled by meansof an S1-MME interface 526 to the E-UTRAN 501.

The SGSN 510 may support legacy access to the UTRAN 517 and/or a GERAN(GSM (Global System for Mobile Communications) EDGE (Enhanced Data Ratesfor GSM Evolution) Radio Access Network) 519. The SGSN 510 is coupledwith the MME 508 via an S3 interface 522. The Serving Gateway 505 iscoupled with the MME 508 via an S11 interface 523.

GERAN is also referred to as 2G and 2.5G. UTRAN is a collective term forthe NodeBs and Radio Network Controllers (RNCs) which make up the UMTSradio access network. This communications network, commonly referred toas 3G, can carry many traffic types from real-time Circuit Switched toIP based Packet Switched. The UTRAN includes at least one NodeB (i.e. aUMTS base station) that is connected to at least one Radio NetworkController (RNC). An RNC provides control functionalities for one ormore NodeBs. A NodeB and an RNC can be the same device, although typicalimplementations have a separate RNC located in a central locationserving multiple NodeBs. An RNC together with its corresponding NodeBsare called the Radio Network Subsystem (RNS). There can be more than oneRNS present per UTRAN.

The E-UTRAN 501 is the 3GPP Radio Access Network for LTE (3.9G) that iscurrently being worked on. The E-UTRA air interface uses OFDMA for thedownlink (i.e. for the transmission direction from the base station tothe mobile terminal) and Single Carrier FDMA (SC-FDMA) for the uplink(i.e. for the transmission direction from the mobile terminal to thebase station). It employs MIMO (Multiple Input Multiple Output) with upto four antennas per (base and user) station. The use of OFDM enablesE-UTRA to be much more flexible in its use of spectrum than the olderCDMA based systems, such as UTRAN. OFDM has a link spectral efficiencygreater than CDMA, and when combined with modulation formats such as64QAM, and techniques as MIMO, E-UTRA is expected to be considerablymore efficient than W-CDMA (Wideband Code Division Multiple Access) withHSDPA (High Speed Downlink Packet Access) and HSUPA (High Speed UplinkPacket Access).

FIG. 6 a and FIG. 6 b show diagrams illustrating the frequency spectrumdescribed by 3GPP LTE specification. FIG. 6 a shows a diagram 601illustrating the use of Frequency Division Duplex (FDD). FIG. 6 b showsa diagram 602 illustrating the use of Time Division Duplex (TDD) toseparate uplink (UL) and downlink (DL) traffic. Frequency DivisionDuplexing (FDD) uses for uplink and downlink a paired spectrum with twodistinct frequency bands 603, 604. The downlink frequency band 603 isseparated from the uplink frequency band 604. Time Division Duplexing(TDD) uses alternating resource portions for Uplink 605 and Downlink 606in the same frequency band. In various aspects of this disclosure, TimeDivision Duplex (TDD) may use alternating uplink portions 605 anddownlink portions 606 in the same frequency band as used by the uplinkfrequency band in the Frequency Division Duplex (FDD) shown in FIG. 6 a.In various aspects of this disclosure, the frequency band used for thealternating uplink portions 605 and downlink portions 606 may be thesame frequency band as the downlink frequency band used in the FrequencyDivision Duplex (FDD) method.

FIG. 7 shows a communication system 700 with a first communicationterminal device 702 (UE) and a second communication terminal device 703(UE) having established a direct communication terminal device tocommunication terminal device communication connection 704 (D2D)bypassing a radio access network according to an aspect of thisdisclosure. A base station 701 (eNB), also referred to herein ascommunication device, may be part of a communication network asdescribed with reference to FIG. 1.

Direct UE-to-UE Communication may also be referred to as“Device-to-Device Communication” or “D2D Communication”. There are inprinciple two alternatives to realize such a direct communication pathbetween mobile devices: the D2D air interface 704 (Ud) may be realizedby some type of short range technology, such as e.g. Bluetooth or WiFi,or by re-using the LTE-TDD flavor of the LTE technology.

For direct UE-to-UE Communication TDD has many benefits over FDD (by wayof example, the same channel characteristics for the transmission pathand reception path can be anticipated, and channel estimation usingclosed loop principles is not needed, etc.).

By way of example, mobile devices (also referred herein as communicationterminal devices) that are residing in coverage of an LTE-FDD cell, andthat want to engage in a direct TDD-based UE-to-UE communication in oneof the frequency bands of the radio cell are exposed to interferencecaused by traffic over the Uu interface 705 in this radio cell. At thesame time the D2D traffic over the Ud interface 705 sourced by thesetypes of D2D-UEs 702, 703 may also cause some (local) interference inthe DL or UL band of the radio cell for other UEs being served over theUu interface 705.

Alternatively, two UEs 702, 703 in RRC_IDLE may be camping on the samebase station. At some point in time the two UEs 703, 703 may detect thatthey are in close proximity and that their D2D technologies would enabledirect exchange of data over the Ud interface 704.

FIG. 8 shows a communication terminal device 800.

The communication terminal device 800 may include a cellular wide arearadio communication technology circuit 801. The cellular wide area radiocommunication technology circuit 801 may be configured to provide acommunication according to a cellular wide area radio communicationtechnology. The communication terminal device 800 may further include acircuit 802. The circuit 802 may be configured to provide a directcommunication terminal device to communication terminal devicecommunication (D2D) bypassing a radio access network according toinformation received via the radio access network. The communicationterminal device 800 may further include a message generator 803. Themessage generator 803 may be configured to generate a message totransmit to a base station. The message may include at least one messagefield specifying information about at least one capability to providethe direct communication terminal device to communication terminaldevice communication of the communication terminal device. The messagemay be generated for a network communication protocol. By way ofexample, the message may be one of an access stratum communicationprotocol message and a non access stratum communication protocolmessage. The cellular wide area radio communication technology circuit801, the circuit 802 and the message generator 803 may be coupled witheach other via a connection 804 (e.g. a cable, and the like).

Furthermore, the message may include information indicating whether thecommunication terminal is capable to provide the direct communicationterminal device to communication terminal device communication.

At least one new parameter may be added to the UE-EUTRA-CapabilityInformation Element (IE) defined in E-UTRA User Equipment Radio AccessCapabilities. It may further be specified that a mobile device that iscapable of direct UE-to-UE communication shall add this parameter to thelist of its radio capabilities.

A new parameter may be “D2D-Capable”, which indicates that the mobiledevice is capable of direct UE-to-UE communication. The possible valuerange for this parameter may be true or false.

The content of the parameter may be as follows:

D2D-Capable::=BOOLEAN

The message may include information indicating what kind of directcommunication terminal device to communication terminal devicecommunication the communication terminal is supporting.

A further new parameter may be “Supported-D2D-Technology”, whichindicates which kind of direct communication terminal device tocommunication terminal device communication the mobile device maysupport. The possible value range for this parameter may be WiFi and/orBluetooth and/or LTE-Direct. If the mobile device does not support D2D,this may be indicated by the absence of this parameter.

The content of the parameter may be as follows:

Supported-D2D-Technology::=ENUMERATED {WiFi, Bluetooth, LTE-Direct}

The message may include information indicating whether the communicationterminal device is able to detect a further communication terminal fordirect communication terminal device to communication terminal devicecommunication in proximity to it.

The message may include information indicating whether the communicationterminal device is capable of providing a direct communication terminaldevice to communication terminal device communication.

The message may include information indicating whether the communicationterminal device is able to engage in direct communication terminaldevice to communication terminal device communication.

A further new parameter may be “Supported-D2D-Service”, which indicates,whether the mobile device is able to detect a further mobile device. Thepossible value range for this parameter may be Proximity-Detectionand/or Communication.

The parameters described above may be used alone or in conjunction whicheach other. The parameter “Supported-D2D-Service” may be used inconjunction with the previous ones.

The content of the parameter may be as follows:

Supported-D2D-Services::=ENUMERATED {Proximity-Detection, Communication}

A set of D2D related parameters (“container”) may be added to theUE-EUTRA-Capability Information Element (IE) and it may be specifiedthat a mobile device that is capable of direct UE-to-UE communicationshall add this set of D2D parameters to the list of its radiocapabilities.

The new Container D2D-Capabilities with a set of D2D parameters may beas follows:

D2D-Capabilities ::= SEQUENCE {  D2D-Proximity-Detection ::= BOOLEAN; D2D-Communication ::= BOOLEAN;  D2D-and-LTE-in-Parallel ::= BOOLEAN; Supported-D2D-Technology ::= ENUMERATED {WiFi, Bluetooth, LTE- Direct};  }

In the exemplary container detailed above, the parameterD2D-and-LTE-in-Parallel set to “true” may for instance indicate that themobile device is capable of acting as a mobile relay node. The term“acting as a mobile relay node” may mean, that the mobile device may becapable of sharing its connection over the LTE Uu interface 705 into thecore network with other mobile devices it is connected to over the D2DUd interface 704 for the exchange of user data (for instance atapplication layer). Likewise, the combination of the parameterD2D-Proximity-Detection set to “true” and the parameterD2D-Communication set to “false” may for instance indicate that themobile device is capable of detecting the proximity of other mobiledevices in its vicinity via D2D technology, but not of exchanging userdata at application layer (such as voice or video calls). If proximityto other devices is found the infrastructure elements of the mobilecommunication network may be informed by the mobile device as configuredby the MNO.

As an alternative, the new Container D2D-Capabilities with a set of D2Dparameters may be as follows:

 D2D-Capabilities ::= SEQUENCE {   WiFi ::= SEQUENCE {   D2D-Proximity-Detection ::= BOOLEAN;    D2D-Communication ::=BOOLEAN;    Version ::= ENUMERATED {802.11, 802.11a, 802.11b, 802.11g,802.11h, 802.11n, 802.11ac, 802.11ad}   }   Bluetooth ::= SEQUENCE {   D2D-Proximity-Detection ::= BOOLEAN;    D2D-Communication ::=BOOLEAN;    Version ::= ENUMERATED { BT1.0, BT1.0B, BT1.1, BT1.2, BT2.0,BT2.0EDR, BT2.1, BT2.1EDR, BT3.0, BT3.0HS, BT3.0EDR, BT4.0}   }  LTE-Direct ::= SEQUENCE {    D2D-Proximity-Detection ::= BOOLEAN;   D2D-Communication ::= BOOLEAN;    D2D-and-LTE-in-Parallel ::=BOOLEAN;    Version ::= ENUMERATED {Rel-8, Rel-9, Rel-10, Rel-10CA,Rel-11, Rel-11CA, Rel-12, Rel-12CA}    Supported-Bands-for-D2D ::=ENUMERATED {I, II, III, IV, V, VI, VII, . . .}    D2D-Bandwidth ::=ENUMERATED {n6, n15, n25, n50, n75, n100}    D2D-in-Paired-Spectrum ::=ENUMERATED {LTE-FDD-UL, LTE-FDD-DL};    }   }

The encoding details of the parameters discussed in the example aboveare according to E-UTRA User Equipment Radio Access Capabilities andE-UTRA Radio Resource Control (RRC) Protocol Specification. TheUE-EUTRA-Capability IE is commonly used to convey the E-UTRA UE RadioAccess Capability Parameters (for optional features) and the FeatureGroup Indicators (for mandatory features within a feature group) to theNW. It may be transferred in E-UTRA or in another RAT.

Furthermore, the message may be part of a feature group indicatormessage to the radio access network.

The (mandatory) D2D-Capabilities may at least be partially groupedaccording to the FGI (Feature Group Indicator) concept in LTE, and—ifmandatory—conveyed as part of the Feature Group Indicators (FGI) to thenetwork. All the functionalities defined within the fieldfeatureGroupIndicators defined in E-UTRA Radio Resource Control (RRC)Protocol Specification may be mandatory for the UE, if the relatedcapability (for example, frequency band, RAT, SR-VCC or Inter-RAT ANR)is supported.

In case of a signalling by means of the FGI concept the Feature GroupIndicator may be as follows:

featureGroupInd BIT STRING (SIZE (32))

For a specific indicator, if all functionalities for a feature grouphave been implemented and tested, the UE shall set the indicator as one(1), else (i.e. if any one of the functionalities in a Feature Grouphave not been implemented or tested), the UE shall set the indicator aszero (0). The various “D2D Capabilities” of a mobile device may becomepart of at least one of the Feature Groups defined in E-UTRA RadioResource Control (RRC) Protocol Specification.

The short range radio communication circuit may be configured to providethe direct communication terminal device to communication terminaldevice communication according to one of a Bluetooth radiocommunication, an Ultra Wide Band radio communication, a Wireless LocalArea Network radio communication, and a Long Term Evolution-Directcommunication.

The circuit may further be configured to invite and/or add a furthercommunication terminal device to a direct communication terminal deviceto communication terminal device communication according to informationreceived via the radio access network.

The circuit may further be configured to offer a connection to othercommunication terminal devices that are connected to the communicationterminal device via the short range radio communication circuit toconnect into the mobile network operator's core network (e.g. when thecommunication terminal device is acting as a mobile relay node).

The circuit may be configured to offer a connection to othercommunication terminal devices that are connected to the communicationterminal device via the short range radio communication circuit toconnect into the mobile network operator's core network based oninformation received via the radio access network.

Mobile devices that are capable of engaging in a direct UE-to-UEcommunication may be enabled to indicate their D2D capabilities to thebase station. A first portion of the capability indication may be useddirectly by the base station (or generally speaking, by an entity of theRadio Access Network (RAN)); another part of capability information maybe used to inform corresponding Core Network (CN) entities, such as (incase of LTE) the MME or the HSS, about a UE's D2D capabilities.

The mobile devices' D2D capability information may be used forcontrolling the formation of D2D clusters, e.g. the NW is enabled tomonitor whether an ongoing cellular connection could be handed over to adirect D2D connection.

Furthermore, the mobile devices' D2D capability information may be usedfor selecting D2D cluster members, e.g. the NW is enabled to distinguishD2D-capable mobile devices from non-D2D-capable devices in mobilityprocedures, such as handover.

The mobile devices' D2D capability information may be used for adjustingthe resource assignment for D2D in a cell according to the mobiledevices' capabilities.

For instance, mobile devices (UEs) that are residing in coverage of e.g.an LTE-FDD (Frequency Division Duplex) cell, and want to engage in adirect e.g. TDD-based (Time Division Duplex) UE-to-UE communication(D2D) in one of the frequency bands of said cell may be exposed tointerference caused by traffic over the air interface (Uu interface) inthis radio cell. At the same time, the D2D traffic over the UE-to-UEinterface may also cause some, e.g. local interference for other UEsbeing served over the Uu interface.

In order to avoid or at least to minimize interferences between UEs orgroups of UEs, the UE may further include a controller. The controllermay be configured to manage radio resources for a cellular wide arearadio communication connection based on radio resources at least one ofprovided or to be provided for a direct communication terminal device tocommunication terminal device communication bypassing a radio accessnetwork.

The UE (also referred to herein as communication terminal device) maysend information to the base station (also referred to herein ascommunication device), which will help the base station to reserve andassign the right amount and the right type of resources and to selectthe right periodicity, respectively. Alternatively, the base station maydetect interferences on its own. The base station may send a responsewith the granted resource allocation in one of the cell's frequencybands (e.g., in the DL (downlink) or UL (uplink) band) for D2Dcommunication back to the UE. The base station may for example useexplicit or implicit resource allocation rules for informing the UEabout free and/or occupied (i.e. used) resources.

In general, the indication of the D2D capabilities to the network isadvantageous, as it enables the NW to exploit the benefits of directUE-to-UE communication more efficiently. The handling of thisinformation among infrastructure elements (RAN and CN), and thedefinition of new message flows (e.g., early abortion in case a UE isnot capable of D2D) to exploit this knowledge in the CN (core network)or in the RAN (radio access network) may allow efficient provisioning ofD2D services.

FIG. 9 shows a flow diagramm 900 illustrating a UE capability transfer.

The procedure for the transfer of UE radio access capability informationfrom the UE 901 to E-UTRAN 902. If the UE 901 has changed its E-UTRANradio access capabilities, the UE 901 shall request higher layers toinitiate the necessary NAS procedures that would result in the update ofUE 901 radio access capabilities using a new RRC connection. E-UTRAN 902initiates the procedure in 903 to a UE 901 in RRC_CONNECTED when itneeds (additional) UE radio access capability information. In 904 the UE902 send back the UE radio access capability information to E-UTRAN 902.

FIG. 10 shows a communication terminal device 1000.

The communication terminal device 100 may include a cellular wide arearadio communication technology circuit 1001. The cellular wide arearadio communication technology circuit 1001 may be configured to providea communication connection according to a cellular wide area radiocommunication technology. The communication connection may be a cellularwide area radio communication connection between the communicationterminal device (e.g., a mobile device) and a communication device(e.g., a base station) of a cellular wide area radio communicationnetwork. The communication terminal device 1000 may further include acircuit 1002. The circuit 1002 may be configured to provide a directcommunication terminal device to communication terminal devicecommunication connection bypassing a radio access network according toinformation received via the radio access network. The information mayinclude instructions controlling a switching from the directcommunication terminal device to communication terminal devicecommunication connection to a cellular wide area radio communicationconnection, or from the cellular wide area radio communicationconnection to a direct communication terminal device to communicationterminal device communication connection. The communication terminaldevice 1000 may further include a message generator 1004. The messagegenerator 1004 may be configured to generate a message to transmit to abase station via the radio access network. The message may include atleast one message field specifying information about at least onecapability to provide the direct communication terminal device tocommunication terminal device communication of the communicationterminal device. The cellular wide area radio communication technologycircuit 1001, the circuit 1002 and the message generator 1003 may becoupled with each other via a connection 1004 (e.g. a cable, and thelike).

The message may include information indicating whether the communicationterminal is capable to provide the direct communication terminal deviceto communication terminal device communication.

The message may include information indicating which kind of directcommunication terminal device to communication terminal devicecommunication the communication terminal is supporting.

The message may include information indicating whether the communicationterminal device is able to detect a further communication terminal fordirect communication terminal device to communication terminal devicecommunication in proximity to it.

The message may be part of a feature group indicator message to theradio access network.

Furthermore, the short range radio communication circuit may beconfigured to provide the direct communication terminal device tocommunication terminal device communication according to one of aBluetooth radio communication, an Ultra Wide Band radio communication, aWireless Local Area Network radio communication, and a Long TermEvolution-Direct communication.

The circuit may further be configured to offer a connection to othercommunication terminal devices that are connected to the communicationterminal device via the short range radio communication circuit toconnect into the mobile network operator's core network.

The circuit may further be configured to offer a connection to othercommunication terminal devices that are connected to the communicationterminal device via the short range radio communication circuit toconnect into the mobile network operator's core network based oninformation received via the radio access network.

FIG. 11 shows a communication device 1100.

The communication device 1100 may include a cellular wide area radiocommunication technology circuit 1101. The cellular wide area radiocommunication technology circuit 1101 may be configured to provide acommunication according to a cellular wide area radio communicationtechnology. The communication device 1100 may further include acontroller 1102. The controller 1102 may be configured to manage adirect communication terminal device to communication terminal devicecommunication bypassing a radio access network based on a message. Themessage may include at least one message field specifying informationabout at least one capability to provide the direct communicationterminal device to communication terminal device communication of atleast one communication terminal device. The cellular wide area radiocommunication technology circuit 1101 and the controller 1102 may becoupled with each other via a connection 1103 (e.g. a cable, and thelike).

The controller may further be configured to extract from the messagereceived from at least one communication terminal device information tobe transmitted to a communication network server.

Furthermore, the communication device may further include a storagecircuit. The storage circuit may be configured to store informationreceived from a communication terminal device about at least onecapability to provide a direct communication terminal device tocommunication terminal device communication of the communicationterminal device.

The controller may further be configured to transmit an initiationmessage via the radio access network to a first communication terminaldevice to provide a direct communication terminal device tocommunication terminal device communication between the firstcommunication terminal device and a second communication terminaldevice.

The communication device may further include a transmitter. Thetransmitter may be configured to transmit the initiation message to thefirst communication terminal device upon a request of a secondcommunication terminal device for a direct communication terminal deviceto communication terminal device communication.

The storage circuit may further be configured to store information aboutthe capability of the communication terminal devices to provide a directcommunication terminal device to communication terminal devicecommunication.

FIG. 12 shows a communication network server 1200.

The communication network server 1200 may include a storage circuit1201. The storage circuit 1201 may be configured to store informationreceived from a communication device. The information may relate to userdata of a communication terminal capable to provide a directcommunication terminal device to communication terminal devicecommunication.

The network server may include a controller 1202. The controller may beconfigured to manage the storage unit. The controller may further beconfigured to manage reception and transmission of information at thestorage unit.

In various aspects of this disclosure, the network server may be a homesubscriber server (HSS).

In various aspects of this disclosure, the network server may be aMobility Management Entity (MME) such as MME 109 illustrated in FIG. 1.

FIG. 13 shows a flow diagram 1300 illustrating a method for controllinga communication terminal.

The method may include, in 1301, providing a communication according toa cellular wide area radio communication technology. The method mayfurther include in 1302 providing a direct communication terminal deviceto communication terminal device communication bypassing a radio accessnetwork according to information received via the radio access network.The method may further include in 1303 generating a message to transmitto a base station. The message may include at least one message fieldspecifying information about at least one capability to provide thedirect communication terminal device to communication terminal devicecommunication of the communication terminal device. The message may begenerated for a network communication protocol. By way of example, themessage may be one of a non access stratum communication protocolmessage and an access stratum communication protocol message.

The method may further include indicating whether the communicationterminal device is able to detect a further communication terminal fordirect communication terminal device to communication terminal devicecommunication in proximity to it.

The method may further include indicating whether the communicationterminal is capable of providing the direct communication terminaldevice to communication terminal device communication.

The method may further include indicating whether the communicationterminal device is able to engage in direct communication terminaldevice to communication terminal device communication.

The method may further include indicating which kind of directcommunication terminal device to communication terminal devicecommunication the communication terminal is supporting.

The method may further include indicating whether the communicationterminal device is able to detect a further communication terminal fordirect communication terminal device to communication terminal devicecommunication in proximity to it.

The method may further include providing the direct communicationterminal device to communication terminal device communication accordingto one of a Bluetooth radio communication, an Ultra Wide Band radiocommunication, a Wireless Local Area Network radio communication, and aLong Term Evolution-Direct communication.

The method may further include using a time division duplex basedcommunication in the uplink or downlink frequency band of the frequencydivision duplex based communication, used by the communication device toprovide a communication according to a cellular wide area radiocommunication technology, for the direct communication terminal deviceto communication terminal device communication.

The method may further include transmitting the information received viathe radio access network to the communication terminal upon a requestfor a direct communication terminal device to communication terminaldevice communication of a further communication terminal.

The mobile devices' D2D capabilities may be sent from the mobile device(UE) to the Base Station (eNB) in a first step. The mobile device (UE)may be capable of building a data structure for its D2D capabilitiesincluding or consisting of multiple components, and of tagging saidcomponents for different recipients (for example, a first part of themobile device's D2D capabilities may be destined for the RAN, while asecond part of the data structure may be destined for the CN). The basestation (eNB) may be responsible for extracting and storing those partsof the mobile devices' direct UE-to-UE communication capabilities thatare related to scheduling and resource assignment in the current cell(and in case of handover also in neighbouring cells).

In a second step, the base station (eNB) may send those parts of themobile devices' direct UE-to-UE communication capabilities that are ofgeneral nature and/or related to mobility management (in particularmobility between 3GPP access networks) to the MME (Mobility ManagementEntity). The HSS (Home Subscriber Server) may be involved in theadministration process, too. It may store user data related to D2D. ThisData may indicate if the user is generally allowed as per his contractto engage in direct UE-to-UE communication.

The UE Capabilities may for example be used for Proximity Detection. Itmay be assumed that a given UE is currently residing in RRC_IDLE and itmay further be assumed that the UE was residing in RRC_CONNECTED before,so that it had an opportunity to indicate its capabilities to theinfrastructure side of the mobile communication network (NW).

The NW may decide (e.g., based on an incoming request at higher layerstriggered by a connection request from a second UE) that the UE shallperform proximity detection. Before the NW may page the UE to trigger anRRC state transition, the NW may use the mobile devices' direct UE-to-UEcommunication capabilities stored in the core network (e.g., in the MMEor HSS) to find out if the UE in question is capable of D2D proximitydetection. If the result of this inquiry is positive, the core network(MME) may kick off the RRC Connection Establishment procedure in the RAN(eNB), so that the UE in question may be requested to perform D2Dproximity detection and—if proximity to the second UE was found—mayreport its findings. If the result of the inquiry is negative, the NWmay answer the received request right away, because it may know from themobile devices' D2D capabilities that D2D may generally be not supported(or that proximity detection is not supported). All the signalling inconjunction with the RRC Connection Establishment procedure in the RANmay thus be avoided and the UE may save a lot of energy.

The UE Capabilities may be used for the formation of a D2D cluster (i.e.a new local D2D network). It may be assumed that a given UE is currentlyresiding in RRC_IDLE and it may further be assumed that the UE wasresiding in RRC_CONNECTED before, so that it had an opportunity toindicate its capabilities to the infrastructure side of the mobilecommunication network (NW).

The NW may decide (e.g., based on an incoming request at higher layerstriggered by a connection request from a second UE) that the UE inquestion shall form a new local D2D network. Before the NW may page theUE to trigger an RRC state transition, the NW may use the mobiledevices' direct UE-to-UE communication capabilities stored in the corenetwork (e.g., in the MME or HSS) to find out if the UE in question iscapable of local D2D network formation. If the result of this inquiry ispositive, the core network (MME) may kick off the RRC ConnectionEstablishment procedure in the RAN (eNB), so that the UE in question canbe instructed to form a new local D2D network (e.g., with the secondUE). If the result of this inquiry is negative, the NW can answer thereceived request right away, because it may know from the mobiledevices' D2D capabilities that formation of a D2D network is generallynot supported by the UE in question. All the signalling in conjunctionwith the RRC Connection Establishment procedure in the RAN can beavoided and the UE may save a lot of energy.

The UE Capabilities may be used for Resource Allocation.

It may be assumed that a given UE is currently residing in RRC_IDLE andit may further be assumed that the UE was residing in RRC_CONNECTEDbefore, so that it had an opportunity to indicate its capabilities tothe infrastructure side of the mobile communication network (NW).

The NW may decide (e.g., based on an incoming request at higher layerstriggered by a connection request from a second UE) that the UE inquestion is supposed to engage in direct UE-to-UE communication in analready existing local D2D network. Before the NW may page the UE totrigger an RRC state transition, the NW may use the mobile devices'direct UE-to-UE communication capabilities stored in the core network(e.g., in the MME or HSS) to find out if the UE in question issupporting the frequency band used by the local D2D network. If theresult of this inquiry is positive, the core network (MME) may kick offthe RRC Connection Establishment procedure in the RAN (eNB), so that theUE in question can be instructed to join the existing local D2D network.If the result of this inquiry is negative, the NW can answer thereceived request right away, because it may know from the mobiledevices' D2D capabilities what D2D frequency bands are supported. Allthe signalling in conjunction with the RRC Connection Establishmentprocedure in the RAN to instruct the UE can be avoided and the UE maysave a lot of energy.

While the invention has been particularly shown and described withreference to specific embodiments, it should be understood by thoseskilled in the art that various changes in form and detail may be madetherein without departing from the spirit and scope of the invention asdefined by the appended claims. The scope of the invention is thusindicated by the appended claims and all changes which come within themeaning and range of equivalency of the claims are therefore intended tobe embraced.

What is claimed is:
 1. A communication terminal device comprising: acellular wide area radio communication technology circuit to provide acommunication according to a cellular wide area radio communicationtechnology employed by an evolved universal terrestrial radio accessnetwork (E-UTRAN); a circuit to provide a direct communication terminaldevice to communication terminal device communication that is to bypassthe E-UTRAN according to information received via the E UTRAN; and amessage generator to generate a message to transmit to an enhanced nodeB (eNB) of the E-UTRAN, wherein the message includes at least onemessage field to specify information of at least one capability toprovide the direct communication terminal device to communicationterminal device communication of the communication terminal device,wherein the message is generated for a network communication protocol,wherein the message includes a network capability information element(IE) to indicate whether the communication terminal device is able todetect a proximate communication terminal device for directcommunication terminal device to communication terminal devicecommunication.
 2. The communication terminal device according to claim1, wherein the message comprises information to indicate whether thecommunication terminal is capable of providing the direct communicationterminal device to communication terminal device communication.
 3. Thecommunication terminal device according to claim 1, wherein the messagecomprises information to indicate whether the communication terminal iscapable of providing the direct communication terminal device tocommunication terminal device communication.
 4. The communicationterminal device according to claim 1, wherein the message comprisesinformation to indicate whether the communication terminal device isable to engage in direct communication terminal device to communicationterminal device communication.
 5. The communication terminal deviceaccording to claim 1, wherein the message is part of a feature groupindicator message to the E-UTRAN.
 6. The communication terminal deviceaccording to claim 1, wherein the circuit is to provide the directcommunication terminal device to communication terminal devicecommunication according to one of the following: a Bluetooth radiocommunication; an Ultra Wide Band radio communication; a Wireless LocalArea Network radio communication; and a Long Term Evolution-Directcommunication.
 7. The communication terminal device according to claim1, wherein the circuit is to add a further communication terminal deviceto a direct communication terminal device to communication terminaldevice communication according to information received via the radioaccess network.
 8. The communication terminal device according to claim7, wherein the network capability IE is further to indicate an abilityto offer a connection to other communication terminal devices that areconnected to the communication terminal device via the directcommunication terminal device to communication terminal devicecommunication to connect into the mobile network operator's core networkbased on information received via the radio access network.
 9. Thecommunication terminal device according to claim 1, wherein the networkcapability IE is further to indicate an ability to offer a connection toother communication terminal devices that are connected to thecommunication terminal device via the direct communication terminaldevice to communication terminal device communication to connect intothe mobile network operator's core network.
 10. The communicationterminal device according to claim 1, wherein the network communicationprotocol includes non access communication protocol and access stratumcommunication protocol.
 11. A communication terminal device comprising:a cellular wide area radio communication technology circuit to provide acommunication connection according to a cellular wide area radiocommunication technology employed by an evolved universal terrestrialradio access network (E-UTRAN); a circuit to provide a directcommunication terminal device to communication terminal devicecommunication connection bypassing the E-UTRAN according to informationreceived via the E-UTRAN, wherein the information comprises instructionsto control a switching from the direct communication terminal device tocommunication terminal device communication connection to a cellularwide area radio communication connection or from the cellular wide arearadio communication connection to a direct communication terminal deviceto communication terminal device communication connection; and a messagegenerator to generate a message to transmit to an enhanced node B of theE-UTRAN, wherein the message includes at least one message field tospecify information about at least one capability to provide the directcommunication terminal device to communication terminal devicecommunication of the communication terminal device, wherein the messageincludes a network capability information element (IE) to indicatewhether the communication terminal device is able to offer a connectionto other communication terminal devices that are connected to thecommunication terminal device via the direct communication terminaldevice to communication terminal device communication to connect into amobile network operator's core network.
 12. The communication terminaldevice according to claim 11, wherein the message comprises informationto indicate whether the communication terminal is capable of providingthe direct communication terminal device to communication terminaldevice communication.
 13. The communication terminal device according toclaim 11, wherein the message comprises information to indicate one ormore types of wireless technologies the communication terminal devicesupports to provide direct communication terminal device tocommunication terminal device communication.
 14. The communicationterminal device according to claim 11, wherein the message comprisesinformation to indicate one or more types of wireless technologies thecommunication terminal device supports to provide the directcommunication terminal device to communication terminal devicecommunication.
 15. The communication terminal device according to claim11, wherein the message comprises information to indicate whether thecommunicate on terminal device is able to engage in direct communicationterminal device to communication terminal device communication.
 16. Thecommunication terminal device according to claim 11, wherein the messageis part of a feature group indicator message to the radio accessnetwork.
 17. The communication terminal device according to claim 16,wherein the circuit is to offer a connection to other communicationterminal devices that are connected to the communication terminal devicevia the direct communication terminal device to communication terminaldevice communication to connect into the mobile network operator's corenetwork based on information received via the radio access network. 18.The communication terminal device according to claim 11, wherein theshort range radio communication circuit is to provide the directcommunication terminal device to communication terminal devicecommunication according to one of the following: a Bluetooth radiocommunication; an Ultra Wide Band radio communication; a Wireless LocalArea Network radio communication; and a Long Term Evolution-Directcommunication.
 19. The communication terminal device according to claim11, wherein the circuit is to offer a connection to other communicationterminal devices that are connected to the communication terminal devicevia the direct communication terminal device to communication terminaldevice communication to connect into the mobile network operator's corenetwork.
 20. A communication network server of a core network,comprising: a storage circuit to store information received from acommunication device; wherein the information relates to user data of acommunication terminal capable to provide a direct communicationterminal device to communication terminal device communication, whereinthe information is to indicate whether the communication device is ableto detect a proximate communication device for direct communicationdevice to communication device communication.
 21. One or morenon-transitory computer readable media having instructions that, whenexecuted, result in a user equipment (UE): generating a UE capabilitymessage that includes at least one parameter to indicate a capability ofthe UE to detect a proximate device with which the UE may engage indirect device-to-device (D2D) communication; transmitting the message toan evolved universal terrestrial radio access network (E-UTRAN) using acellular wide area radio communication technology circuit of the UE; andreceiving information from the E-UTRAN to facilitate detection of aproximate device and/or engagement in direct D2D communication.
 22. Theone or more non-transitory computer readable media of claim 21, whereinthe instructions, when executed, further result in the UE: transmittingthe message to a mobility management entity (MME) through the E-UTRAN.23. The one or more non-transitory computer readable media of claim 21,wherein the at least one parameter is to further indicate one or moreD2D technologies supported by the UE.
 24. The one or more non-transitorycomputer readable media of claim 21, wherein the UE capability messageis a non-access stratum communication protocol message.
 25. The one ormore non-transitory computer readable media of claim 21, wherein the atleast one parameter is to indicate a capability of the UE to act as amobile relay node.
 26. A mobility management entity (MME) comprising: acontroller to receive capability information to indicate a capability ofa user equipment (UE) to detect a proximate device with which the UE mayengage in direct device-to-device (D2D) communication; and a storagecircuit to store the received capability information.
 27. The MME ofclaim 26, wherein the controller is further to control an evolveduniversal terrestrial radio access network (E-UTRAN) based on the storedcapability information.
 28. The MME of claim 26, wherein the controlleris to receive the capability information as a non-access stratumcommunication protocol message from the UE.